Method and apparatus for producing fibrous articles



June 1932- I 4 R. s. FROBISI-UIER 1,861,849

METHOD AND APPARATUS FOR PRODUCING FI BROUS ARTICLES Filed May 20, 1930' 7 heets shet 1 T fhz/enlohr. Ralph SFFOMT W' j Atys.

June 7, 1932. R. s; FROBISHIER METHOD AND APPARATUS FOR PRODUCING FIBROUS ARTICLES Filed May 20, 1930 '7 Sheets-Sheet 2 Fig. 2.

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METHOD AND APPARATUS FOR PRODUCING FIBROUS ARTICLES Filed May 20, 1950 7 Sheets-Sheet 3 IfibfiZiOl. Raga/2 S. r0621; r 19% v Aitys.

June 7,1932. f s FRoBls HER 1,861,849

METHOD AND APPARATUS FOR PRODUCING FIBRQUS ARTICLES Filed May 20, 1950 '7 Sheets-Sheet 4 Fgg. 6.

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' METHOD AND APPARATUS FOR PRODUCING FfIBROUS ARTICLES Fil d May-2Q, 1930 7 Sheets-Sheet 6 F A20 (j In v'en ton Patented June 7, 1932 UNITED STATES PATENT OFFICE RALIjH S. FROBISHER, OF PORTSMOUTH, NEW HAMIPSHIRE, ASSIGNOR TO I BEMIS IN- DUSTRIES, INCORPORATED, OF BOSTON, MASSACHUSETTS, A CORPORATION OF DELA- wean Y Application filed May 20,

the patent to Albert F. Bemis No. 1,618,696,

granted February 22, 1927, and his copending application Serial'No. 72,676, filed De-- cember 2, 1925. This invention is particul'arly'adva'ntageous in permitting the formation of relatively large, thick and bulky units,

which may be non-circular, of felted fibrous material from. a water suspension or pulp.

, The latter may include about the same proportions of vegetable or wood fibersv and water as are employed in paper pulps, or mineral fibers such as mineral wool may be substituted for some. of the vegetable fibers. If

desired, the units may be substantially a story in height, may have a thickness of the order of ordinary walls, being provided with openings as well as marginal recesses which may be brought into registration when the units are assembled in a wall. The openings in the units themselves and the openings provided by the registering recesses may receive monolithic concrete extensions of other parts of the building.

In accordance with the present invention units of this character and similar larger or smaller units may be formed of light felted fibrous material, which is comparatively inexpensive, which affords excellent sound and heat insulation. Relatively large building units or blocks capable of forming large areas of Walls may, when constructed according to my invention, be handled by a single workman, with resulting facility of transport and use. Preferably a differential in pnuematic pressure, i. e., vacuum, is effective i n causing the felting of the fibrous material, being particularly advantageous in aiding uniform distribution of the fibers, proper filling of the form or mold with the same, andin affording excellent felting of the fibers.

My invention aims to provide'for the expe ditious and rapid manufacture of such buildin g units, to provide for the'efiicient handling of the large quantities of material involved and to enable the units to be made of high METHOD AND APPARATUS FOR PRODUCING FIBROUS ARTICLES 1930. Serial N0. 453,993.

quality and structural uniformity. Other objects of the invention and advantages of the resulting improved process and apparatus will be apparent from a consideration ofspecific instances of, the invention explained by this specification and its accomshowing particularly the piping arrangement Fig. 4 is a fragmentary side elevation, with some of the piping removed and other parts partially .broken away, similar in point of view to Fig. 1 and to a larger scale, and showing particularly the lower end of the casing and the forms and distributing ducts,as s' o-.

ciated therewith; i

v Fig. 5 is a fragmentary elevation, partially 1 broken away, of the upper end of the casing and its associated pneumatic manifolds, and

viewing the casing at right angles to 'Figs. '1 and 4;

Fig. 6 is a side elevation, on a larger scale, of one of the rotary distributing ducts, showing diagrammatically the means for rotatably mounting its lower-end and for conveying fibrous stock and drying fluid thereto;

Fig. 7 is a, sectional view of. parts of the apparatus, taken on the line 7-7 of Flg. 1 and on an enlarged scale.

Fig. 8 is a, sectional view of parts of the apparatus, taken on the'line 88 of Flg. 1, and on a larger scale;

Fig. 9 is an end view of a pair of conj ointed} forms I Fig. 10 is an end View of the pair of forms upon a suitable platform, adapted to fac1l1 tate removal of the units from the molds,

and showing diagrammatically 'a way of removing the building units from the molds;

Fig. 11 is a perspective view of a modified building unit capable of being made by improved process and apparatus .of my invention;

I Fig. 12 is an end view of a mold or form suitable for making the modified building "unit of Fig. 11;

Figs. 13 and 14 are side elevations (taken ufactured by means of my improved method and apparatus may be formed or integrated from a fibrous pulp, such as Wood pulp, and may have a central opening 8 throughout its length and two semi-circular grooves 9 on opposite side faces adapted to register with similar grooves upon adjoining units to provide openings parallel to the openings 8. Preferably fiat surfaces 10 are disposed at each side of the grooves 9 to abut or engage similar surfaces of adjoining units to permit v the ready construction of a building wall after the general manner described in the above-identified patent and copendingapplication. v 1

Units of the character illustrated in Fig.-

2' may be conveniently formed in a single manufacturing operation in apparatus including a form having a foraminous outer wall and an inner distributing memberwhich is perforated or foraminous, a suitable pressure differential being provided to cause the flow of fibrous stock into the space between the distributing member and the outer foraminous wall,'and means being provided to permit the subsequent flow of drying air or the like in thesame manner through the wet stock to effect the initial drying of the same; if necessary and as desired special means may be provided to ensure the proper drainage of water from the interior of the form that has received the stock. Apparatus of this character is illustrated in the accompanymg drawings, in WhlCh a vertical casing 11 is arranged to receive a removable form, indicated generally by the numeral 12 (Figs. 4, 5 and 7). Form 12 preferably is arranged to provide for the simultaneous manufacture of a plurality of units, and. in the present embodiment of the invention is illustratedas a double form adapted to receive and shape the pulp into twoseparate fibrous building units. Accordingly, the

form illustrated and described herein comprises two single forms detachably connected and preferably identical.

Referring particularly to Fig. 7, which shows a pair of forms in operative position within the casing 11, one of these single forms or molds preferably comprises vertical perforated plates 14, 15, 16 and 17.

.Plates 14 and 16 are hinged to plate 17 by the hinges 18 and 19 respectively. Vertical perforated angle bars 20 and 21 are riveted to the vertical plate 14, and vertical angle bars 22 and 23 are riveted to the vertical plate 16. Horizontal perforated angle bars 24 and 25, riveted respectively to vertical plates 14 and 16, serve as reinforcing spacers for the vertical angle bars, and horizontal bolts 31 serve as tie rods for the vertical angle bars. A vertical channel member 26, riveted to the vertical plate 15, provides a reinforced abutment for the ends of the hinged vertical plates 14 and 16. Suitable tie rods 27 pass through the angle bar 20, j

vertical plate 14, channel member 26, vertical plate 16, and the angle bar 22 and, when secured by suitable wedges 28, serve to maintain the form in a tightly closed position. Channel bar 26 and its attached plate 1-5 are, however, detachable from the remainder of the form to facilitate removal of the formed building units as hereinafter explained.

At each side of the form a perforated semicylindrical plate 30 extends inwardly and is secured to the vertical walls of the form by suitable bolts 31. The entire inner sur-.

face of the form is lined with a suitable foraminous material, such as fine wire netting, indicated at 32,:which preferably is discontinuous at the corners of the form so that the form may be swung open without injury to the netting. The form thus constitutes an enclosure having an inner wall surface .of foraminous material which is reinforced by an outer perforated sheet construction and which is adapted to retain fibrous pulp within the form but to permit water or any drying fluid such as air topass outwardly through its walls. The form when in a closed position, as shown in Fig. 7, is adapted to receive the pulp. After the pulp has partially solidified, the form may be opened by removing wedges 28 and swinging the sides of the form about the hinges 18 and 19' until the form is completely open. In this position the fibrous unit may be removed from the form in the manner described hereinafter. Referring to Fig. 7, the two individual forms of the pair are joined by connecting links 33 which may readily be removed in case it is desired to repair either of the forms or to use either of them singly. It is convenient, however, to use the two forms of the pair together, and simultaneously, as a single unit.

sition in the casing 12, surrounds a vertical distributing duct 50 provided with staggered perforations 51'(Figs. 4, 5 and 6) which are larger than the fine meshes of the foraminous material 32 lining the outer walls of the form, and which of the pulp fibers.

The form, when-in its operative position Each form 12, when in its operative popermit the ready passage ill) within the casing 11,. is thus provided with a wall portion having fine perforations, preferably the entire set of four outer walls, as shown, and another wall portion afforded by the distributing duct provided. with very'much larger perforations. I utilize this form to manufacture fibrous articles by creating a pneumatic pressure differential be pressure differential that are employed in" depositing the fiber within the form. In the preferred apparatus and method described herewith, I utilize the same group of large perforations, namely, those in the duct 50, for the admission of drying fluid after these perforations have served to admit pulp stock, and further utilize the same duct 50 as-a conduit for drying fluid after it has been utilized to distribute the pulp stock.

The means employed for creating the pneumatic pressure difierential between the two differently perforated wall portions of the forms may comprise (Figs. 1 and 3) a vacuum pump 81 connected by a pipe 81 to an exhaust chamber which communicates through suction pipe connections 82, 83 and 84 and suction control valves 83 and 84' with upper manifolds 85 and 85' and lower manifolds'86 and 86. These manifolds communicate through oppositely disposed-elbow connections 88 (Fig. 7) with the'interior of casing 11 and hence with the outer foraminous walls of the form 12. The perforations in angle bars 20, 21, 24 and 25 permit the uniform application of the vacuum to all parts of the fora'minous lining 32, so that the manifolds communicate with a vacuum space or jacket surrounding the forms.

A reservoir for pulp stock is designated by numeral 90 (Fig. 1). A; suitable agitator 99 may be provided in the pulp stock reservoir 90 and preferably is driven by motor 7 0. To supply the pulp stock to the forms I have provided a suitable rotary pump 91,

(Figs. 1 and 3) which removes pulp stock from the bottom of the reservoir 90 and directs it through pipe connections 92" and 93 into a vertical duct 94 which communicates with a container 95 for pulp located above the casing 11. A horizontal branch connection 96 provided with a quick acting valve 97 provides a by-pass for pulp between the vertical duct 94 and the pulp reservoir 90, l/Vhen the valve 97 is open all the pulp directed into the vertical duct 94- by the pump 91 will bypass into the reservoir 90, but when the valve 97 is closed the pulp will be forced through the upper portion of the duct 94 into the pulp container 95. By means of this construction the pulp stock may be maintained in motion and thoroughly agitated and in addition may be supplied quickly to the pulp container 95 by merely closing the quick acting valve 97. The opening of valve 97 permits any pulp within the container 95 readily to drain back into the reservoir 90.

Referring to Fig. 5, the upper end of the casing 11- is joined t) and-extends into the pulp stock container 95. The upper ends of the two movable distributing ducts 50 communicate through apertures in a hinged lid 52 with the pulp stock container 95 and provide passages through which pulp stock may flow downwardly from the pulp container 95 into the forms 12 within the casing. A preferred construction for the pulp container 95 is that of a vat having an open top. lVhen pulp has been drained from the pulp container 95, the upper ends of rotary distributing pipes 50 are exposed to the atmosphere and permit atmospheric air to be drawn into and through the formsas a result of the pneumatic pressure difference which is created bemore uniform distribution of pulp stock and air within th forms, and in order to obtain greater flexibility of operation through 111- dependent control of the pulp stock and air entering opposite ends of theforms. Be

neath and abutting the base 53 of casing 11 and directly under the rotary distributing ducts 50 are provided two cross-shaped fittings 54 (Figs. 4 and 6) the vertical passages of which constitute smooth cylindrical bearings for the rotary distributing ducts 50.

Referring to Fig. 6, in which the pipe cross 54 is shown in dotted lines, the lower end of the duct 50 enters and is affixed to a hollow journal 55 which rotates in the bearings provided by the pipe cross 54. The hollow journal 55 is provided with oppositely disposed lateral openings 56 and 57 sufficiently large to insure substantially continuous communication between each of the lateral extensions of the pipe cross and the rotary distributing duct 50 for all angular positions of the latter.

Referring to Fig. 8, lateral horizontal extensions 54 of the two cross-shaped eonnections 54 vcommunicate through ducts 103 and 104 with a horizontal connecting duct 105. A duct 101 connected to pulp stock supply pipe 92 is adapted to supply pulp stock througl'i duct 103 and through ducts 105 and 104 to each of the cross-shaped connections 54. A normally closed valve 150 in duct 101 is adapted to open to communicate .zontal extensions 54'. of

' ing ducts 50, is provided with a quick acting valve 110 communicating withfthe atmosphere. After shutting off the flow of'pulp stock through quick acting valve 106, air may be admitted throughquick acting valve 110 to the lower ends of rotary ducts 50. In this manner the lower ends of forms are provided with an independently controllable supplyof drying fluid.

If desired, provision may be 'made for supplying water to the lower ends of ducts 50 for removing from time to time any accumulation of pulp therein, by connecting a source of water supply l-ll through a valve 112 and pipes 108 and 109 to the two horithe cross-shaped connections 54. i

In order to cause'rotation of the distributing ducts 50 I prefer to provide each'of their hollow journals 55 (Fig. 6) with an integral downwardly extending shaft 59 (Figs. 4 and 6) having its lower end mounted in a bearing 66 (Fig. 4) and to connect these" shafts 59 by means of suitable sprocket chains '72 and 73 with a driving shaft71 adapted to be rotated by the same motor 70 which is utilized to operatethe agitator 99 referred to above.

Since the bottom of the casing 11 is closed, there is a tendency for water to accumulate in its lower part. I To prevent such accumulation, I prefer to provide means for removing water from the bottom of casing 11,

preferably by the provision of a small pipe 120 (Figs. 3 and 8) connected to the interior of the casing at the four bottom corners and extending upwardly and into the vertical suction pipe 83. A suitable valve 121 is pro vided in the pipe 120 (Fig. 3) and a glass section 122 is provided in the pipe to enable.

an operator to determine when the water has ceased to flow therethrough. f

Due to the suction of pump 81, which preferably may be at least of the-order of half an atmosphere, for example, 10 pounds per square inch, water in the casing 11 will be withdrawn therefrom and deposited in the -vacuum chamber 80. This chamber is provided with a suitable water glass 1'80'for indicating the accumulation of'water therein and also with suitable exit connections for discharging its accumulated contents when desired, either into the pulp reservoir 90 or to a suitable drain.

In the carrying out of 'my process and in utilizing the apparatus described above, one of the double forms 12 is inserted into the casing and the lid 52 closed and secured. The valve 97 is open at this stage of the operation and the pulp pumped by pump 91'is caused to travel in-a circuit through ducts 92, 93, 9% and 96 back to the reservoir .90. A pneumatic pressure diflerence is then created between the inner and outer sides of the form by opening the valves 83' and 8 1' in suction pipes 83 and 84 to apply suction to the outer side of the form. If any Water has accumulated in the bottom of the casing 11, it may be removed by opening the valve 121 and allowing the water to be sucked out of the easing through pipe 120. By means of the manifolds 85, 85, 86 and 86', the effect of the .vacuum is applied uniformly to the walls of the casing. closed and the pulp is forced by pump 91 through the upper portion-of duct 94 into the pulp container 95 from whence it is drawn by suction, assisted by gravity, into the two vertical rotarydistributing pipes 50. Valve 106 is then opened and pulp is admitted to the lower ends of the vertical rotary distributing ducts 50. The. spaced holes 51 in the ducts 50 provide for egress of the pulp.

into the forms and the rotary motion of the ducts 50 serves to distribute the pulp with respect to the surrounding foraminous walls. Simultaneously with the supply of pulp to Quick-acting valve 97 is then the forms, water is abstracted from the pulp and removed through the outer perforated walls of the forms by the manifolds 85,

86 and 86, and is collected inthe bottom of the vacuum chamber 80. As a result of this operation the pulp agglomerates in the forms.

After the forms have'been filled with fibrous material in this manner, the supply of pulp is cut oil by closing valve 106 and opening the quick-acting valve 97 Valve, 150 is opened to the atmosphere for a few seconds to permit-pulp remaining-in pipe 101 to be drawn b suction into the Vertical rotary distributing pipes 50. Surplus, pulp in the pulp container passes through pipe 96 into the pulp reservoir 90".

The upper ends of the rotary distributing ducts 50 are then open to the atmosphere and admit air to the upperends of the, distributing-ducts 50. Valve 110 is opened and admits air to the lower ends of ducts 50. The air thus admitted to the ducts 50.,at both ends is drawn through the moistfibrous material in the forms, absorbing and entraining moisture therefrom, and is removed through the manifolds and vacuum chamber. Simultane ously valve 121 may be opened to Withdraw accumulated water from the bottom of the casing. By watching the glass 122 it may be ascertained when all the accumulated water is removed from the bottom of the ca :ing and the valve 121 may then be closed.

After passing the air through the pulp for several minutes the air is shut ofi, the lid 52 t is opened and the forms are removed through the top of the casing 11 and the pulp container 95 by a suitable elevating mechan sm such as a hoist 9!) (Fig. 1). A

guicleway 140 (Fig. 1) may be provided leading to a platform 14 upon which the forms may he while being opened.

Fig. 10 indicates diagrunniatically a way i of removing the agglomerated, but still soft,

- rated at 161, preferably is provided at a some- Lil what lower level than the platform 141 so that a side wall of one form may be swung down thereupon, as shown. The channel bar 26 and its attached perforated plate 15, which normally form one wall of a form but which are detachable therefrom, as explained above, initially serve as a support and base for the building unit upon its removal from the form.

Thus Fig. 10 indicates in dotted line a building unit removed from the remainderof the form and resting upon this channel member and plate. Any suitable additional plat-e or support for the form, herein shown as a channel bar 163, may-then beplaced against the vertical side of the building unit, and the unit and this support then be turned over into the position shown in full lines in Fig. 10. In this way the unit may-be removed without injury thereto and without undue handlin The unit which has been made in the other form of the pair may be removed in a similar manner from the opposite side of the pair of forms. T he units which have been removed from the forms may be slid onto racks in a drying car, indicated at 142, which is then moved into any suitable oven wherein the fibrous building units are thoroughly dried and hardened.

In the method as described for manufacturing these building'units, only a portion of the water has been removed from the pulp while within the form, the remainder being removed subsequently by drying, preferably at super-atmospheric temperature. This division of the drying function is advantageous as it enables a single apparatus as described above to manufacture building units in quick succession, a building unit preferably not being retained within the form after becoming solid enough to support alone its own weight. However, it is within the scope of any invention to'carry the drying process further orto completion, in the form, and to dis-- charge building units from the form in a more nearly or completely dried and hardened state.

It is evident that this invention permits the manufacture of comparatively large and thick fibrous articles, which may be substantially homogeneous and free from laminations or the necessity for employing a large amount of binding material, sizing, or the like. Units of this character are light and excellent sound and heat insulators and have considerable structural strength, particularly when subjected to compressive strains. It is evident that the exact form and shape of the article manufactured in accordance with this process may be widely varied.

For example, the block shown in Fig. 11, which is particularly described and claimed in my copending application Serial N 0.

429,607, filed February 19, 1930, may be manufacture'd according to my invention in the mold 12, shown in Fig. 12, used in connection with the modified form of apparatusshown in Figs. 13 and 14. Referring to Fig. 11, the

building unit shown therein is generally wider and'shorter than that of Fig. 2, has two semi-circular grooves 9" on opposite side faces, and has three lon itudinal openings 8 therethrough instead of the single opening of the unit of Fig. 2.

The mold 12 of Fig. 1.2 to -one half of the pair of molds of Figs. 7 and 9, and the apparatus of Figs. 13 and 14 is generally similar to that of the previously described apparatus. Accordingly certain parts of the mold and other apparatus of this modified structure are designated by refer-- ence characters corresponding to those employed 'in the previously described embodiment, with the addition of a small a.

'Referring to'Fig. 12, the mold 12 preferis generally similar ablv includes vertical perforated plates 14 and 19 connecting plate 17 with plates 14*- .and 16 respectively, hinge 18 connectlng plate 15 with plate 14 a1 1d ang1e bar 26 affixed to plate 15"-. Semi-cyllndrlcal perforated plates 30 are disposed on opposite sides of the mold, and the inner surface of the walls thus formed is lined with suitable foraminous material 32 as 'in the previouslv described embodiment. Suitable exterior reinforcements in the form of perforated angle bars 24 and 25 affixed to plates 14 and 16 -1naylikewise be provided as in the previously described embodiment.

' Suitable apparatus for receiving the form or mold 12 of Fig. 12, and for cooperating therewith in the manufacture of the building units of Fig. 11, is shown in Figs. 13 and 14. This apparatus isgenerally similar to the casing and associated parts shown in Figs. 1 to 8, suitably modified'for the different configuration of the building units of Fig. 11 and may be connected to suitable pulpsupplying means, suction-applying means and driving means, such for example as those described and shown in Figs. 1 and 3. This apparatus of Figs. 13 and 14, which is intended to manufacture one block at a time, comprises generally the casing 11 ,suitable to receive and enclose the form or mold 12 of Fig. 12, the pulp container 95 which preferably is supplied with pulp by connections such as those employed in the previously described embodiment a plurality of rotatable pulp-distributing .ducts 5O (three being shown herein) similar to those of Fig. 0,

manifolds 85. communicating with the interior of the casing 11 and through the pipe 82- with suitable suction apparatus such as provided in the previously described embodiment, and if desired suitable conduits for supplying at will pulp or drying air to the lower ends of the distributing ducts. In the apparatus of Figs. 13 and 14, pulp to be introduced into the casing through the lower ends of the distributing ducts is supplied by pipe 101 -and pipes 104, A valve 106 controls the supply .of pulp through pipe 101 and another valve 110 serves to admit air at will. A connection 120 is preferably also provided for removing accumulated water from the lower end of the casing. The rotary distributing ducts 50 may conveniently be driven from a common source of power by providing their shafts 59, as shown, with ,intermeshing gearing 200 and by providing a drive chain 72" for driving one of these shafts. In this manner alternate ducts 50* are adapted to rotate inoppo'site directions. Preferably in the case of a machine such as is illustrated in Figs. 13 and 14:, the

lower portions of the ducts 50 may be pro-.

v vided with vertically disposed slots 301 in tom of the ducts 50 and through the pulp deposited in the form, and the'form with its contained partly dried building unit finally being removed from the casing.

A way of removing the formed unit from the mold 12 is indicated diagrammatically in Fig. 15. Referring to this figure, the mold may be opened by swinging the sides about hinges 18 19 and 18 and the formed unit removed upon a tray in the form of a chan nel bar 163 Thebloc k may then be dried,

in an oven, as described above.

The employment of a rotar distributing duct 50, in the manner descri ed above, results in the preponderant distribution of the tary core or cores, both in the manufacture of the unit having a. single opening,.such as is illustrated in Fig. 2, or the block illustrated in Fig. '11. the fibers to move towardthe outer foraminous lining of the form causes a somewhat closer aggregation of fibers at the surfaces of the unit, thus providing a somewhat denser structure adjoining the faces of the unit or block.-

Obviously, units manufactured in accordance with the present invention may have a wide variety of uses, not only in the type of building construction disclosed in the aboveidentified patent and copending application of Albert F. Bemis, but also, for example, between the studs of ordinary buildings; These unitsmay be split and/or combined with various flat wall boards to meetvarious insulating requirements.

I claim: 1

1. The art of forming hollow non-circular .fibrous articles by means of a form having an Furthermore, the tendency of inner perforated core and outer meshed walls which comprises introducing pulp into the form under a hydraulic head with a concomitant difference in pneumatic pressure tending to convey pulp particles from the perforated core toward the foraminous walls of the form. I

2. The art of forming hollow non-circular fibrous articles by means of a form having an inner perforated core and outer meshed .walls which comprises introducing pulp into the form under a hydraulic head with a con comitant difference in. pneumatic pressure tending to convey pulp particles from the perforated core toward the foraminous walls of the form while moving the core in order to permit the uniform distribution of the pulp entering the form.

3. The art of forming hollow non -cir cular fibrous articles by means of a form hav- 1 and a perforated core -to produce elongate hollow pulp units, which comprises admitting pulp to the form through the upper part of the core member by subjecting the entering pulp to a hydraulic head and to a differential in pneumatic pressure tending to direct the pulp particles to the foraminous walls of the form, and after this pulp move ment has been initiated introducingadditiona1 pulp to the lower part of the form through the lower part of the core member.

5. The art of employing avertically disposed form having a foraminous outer wall and a perforated core to' produce elongate hollow pulp units which comprises admit-ting pulp to the form through the upper part of the core member by subjecting the entering pulp to a hydraulic head and to a differential in pneumatic pressure tending to direct the pulp particles toward the foraminous walls of -the form, and after this pulp movement has been initiated introducing additional pulp to the lower part of the form, while mov ing the core to permit uniform distribution of the pulp, and thereafter directing a current of drying air from the perforated corethrough the contents of the form to, its foraminous walls.

' 6. The art ofmanufacturing fibrous articles which involves the employment of apparatus havinga perforated core disposed I in a form having foraminous walls, compris ing introduction of pulp to the interior of the-form by subjecting the interior of the core and the exterior of the form to a dilfer ential in pneumatic pressure of the order of a half of an atmosphere, while rotating the perforated core and maintaining the form stationary to efiect the uniform distribution of the pulp in the form. i

7. Apparatus comprising a form having an outer wall of, foraminous material affording if numerous relatively fine interstices, and a movable coredisposed within the form and having a plurality of perforations, means for admitting pulp to the interior of the core whereby it may pass throughthe perforations in the same toward the foraminous walls of the form, and means for subjecting the core and form to a substantial difference in pneumatic pressure, whereby flow of pulp from the core toward the feraminous walls of'the form is induced.

8. Apparatus comprising a form having. foranunous' outer walls, a tubular core disjacket, and means to supply pulp to the projecting end of the core ,wherebythe pulp may be drawn through the openings in the core.

toward the foraminous walls of the form.

9. Apparatus comprising a form having foraniinous outer walls, a tubular'core disposed within the form and rotatable in relation thereto, said core having numerous perforations,a Vacuum acket disposed about the form, means to subject the foraminous walls of the form to a sub-atmospheric pressure by means ofevacuation of the jacket, one end-of the core extending through an end of the jacket, means'to supply pulp to the projecti'ng end of the core whereby the pulp may be drawn through the openings in the core toward the foraminous walls of the form, and means for interrupting the flow'of pulp into the core and then permitting the flow of air into the same. 10. Apparatus of the class describedcom prising a dual form having two sections each of which is provided with outer foraminous Walls, a vacuum jacket arranged to receive the form andto subject the-walls thereof to sub-atmospheric pressure, said jacket having a movable end portion to cover an end of the form, movable cores disposed within the jacket and extending through the sections of the form with ends projecting through the jacket end, means for supplying pulp to the projecting end portions of the movable cores, drains connected to the'lower portion of the jacket, and air ducts connected to the jacket to permit evacuation thereof and air flow through the contents of the forms.

lluApparatu's of the class described comprising a dual form having two sections each of which is provided withouter foraminous walls, a vacuum jacket arranged to receive the form and to subject the walls thereof to sub-atmospheric pressure, said acket having a movable end portion to coveran end of the ranged to permit a unit in the wet formative set 'to be swung outwardly upon one of the walls and removed therefrom to a suitable drying plaque.

12. Apparatus for manufacturing fibrous articles comprising a hollow form having a perforated wall, a condfuitfor admitting successively pulp and a drying fluid to the interior of the form, and means for creating im a pneumatic pressure difference between said conduit and the outer side of said perforated" wall, while causing relative movement between the conduit and wall.

v 13. Apparatus for manufacturing fibrous articles comprising a casing, a closure for its top, a form within said casing removable 7 upon the opening of the closure, a container for'pulp, above said casing, a tubular distributing' member within said form, said closure being provided with an aperture permitting tainer.

.communication between said distributing member and the pulp container while the closure s shut.

14. Apparatus for manufactu 'ing fibrous articles comprising a casing, a closure for its top, a form within said casing removable, upon opening the closure, a container above the casing, a tubular distributing member within said form .and extending through an aperture in said closure into the pulp con-.

15. Apparatus for manufacturing fibrous articles comprising a form having means' for exhausting fluid therefrom and adapted to exhausting fluid therefrom and adapted to f retain pulp therein and a tubular distributing member extending from end to end of said form, means for admitting drying fluid to one end of said distributing member, and separately controllable means for admitting drying fluid to the other end of said distributing member.

17. Apparatus comprising a form having an'outcr wall of foraminous material affording numerous relatively fine interstices'anda plurality of movable cores disposed within the form and each having a plurality of perforations, means for admitting pulp to the interior of the cores whereby it may pass through the perforations toward the forami nous walls of the form, and means for subjecting the cores and form to a substantial differential .in pneumatic pressure whereby flow of pulp from the cores toward the foraminous walls of the form is induced.

18.'Apparatus comprising a form having.

an outer wall of foraminous material affording numerousrelatively fine interstices and a row of movable distributing ducts disposed within the form and each having a plurality of perforations, means for rotating the ducts, means for admitting pulp to the interior of the ducts whereby it may pass through the perforations toward the foraminous walls of the form, and means for subjecting the ducts and form to a substantial difference in pneumatic pressure whereby flow of pulp from the ducts toward the foraminous walls whereby it may pass through theperfgwa tions, the walls of said forms having numerous relatively fine openings, to permit the flow of liquid whereby pulp may be drawnby the suction means into the forms and liquid removed through the openings in the wallsthereof. 4

20. Apparatus for manufacturing a felted fibrous unit with a core opening and grooves therein comprising-a'form having opposite planar walls and walls therebetween with inwardly bulged portions, said walls having numerous fine interstices, a' rotary distributing duct with numerous large perforations therein disposed within the formbetween the bulged wall portions, and a vacuum jacket surrounding the form, means for supplying pulp to the distributing-duct, and

means for applying suction to the vacuum jacket.

.21. Apparatus comprising a pulp vat, a vacuum jacket below the Vat, aforin within the jacket, said form having outer walls reservoira'duct for supplying pulp from the reservoir to the vat,'a shunt between the duct and the vat, a valve in the shunt, the valve when open permitting the flow of pulp from the reservoir into the duct without the passage of the pulp into the vat, the valve when closed permitting the pulp to flow into the vat, and means for imposing a sub-atmospheric pressure uponcthe vacuum jacket whereby when the valve is closed pulp may be supplied to the interior of the form by the distributing duct and whereby, when the valve'is opened, air may be drawn through the duct and through the pulp in the form due to the suction in the jacket.

2:2. Apparatus of the class described com-' prising a vacuum jaeketfa form within the jacket having numerous fine interstices in its 'walls, a distributing duct within the form having numerous perforations larger than theinterstices, means for supplying pulp to the distributing duct including a pulp reservoir, a vacuum pump, a vacuum chamber connected thereto, a pipe connecting. the chamber and the jacket, and an outlet drain at the lower end of the chamber arranged to .return water drawn from'the form to the reservoir, whereby a substantial portion of the water in the pulp thus supplied to the form may be recovered.

23. Apparatus of the class described comprising a. form having'numerous line perforations in its walls, a distributing duct -within the form having numerous perforations larger than those in the walls of the form, the end of the duct projecting out of the form, driving means associated with said end of the duct to impart motion thereto,

and means for supplying pulp to said projecting end of the duct.

24. Apparatus of the class described comprising a form having numerous fine perforations in its walls, a distributing duct within the form having numerous perforations larger than those inthe walls of the form, the end of the duct projecting out of the form, driving means associated with said end of the duct to impart motion thereto, and means for supplying pulp to said projecting end of the duct, said means comprising a casing forming a bearing for the duct and communicating with apulp supply'duct,

the distributing duct having openings therein to register with the supply duct.

Signed by me at Portsmouth, N. 1-1., this tenth day of May, 1930.

RALPH S. FROBISHER. 

